Thrombopoietin mimetics

ABSTRACT

Non-peptide TPO mimetics are disclosed, as well as a method of treating thrombocytopenia, in a mammal, including a human, in need thereof, which comprises administering to such mammal an effective amount of a selected hydroxy-1-azo-naphthalene derivative.

This is a 371 of International Application PCT/US99/30371, Filed Dec.17, 1999, which claims benefit from the following ProvisionalApplication: No. 60/153,364, filed Sep. 10, 1999 and No. 60/112,614,filed Dec. 17, 1998.

FIELD OF THE INVENTION

This invention relates to thrombopoietin (TPO) mimetics and their use aspromoters of thrombopoiesis and megakaryocytopoiesis.

BACKGROUND OF THE INVENTION

Megakaryocytes are bone marrow-derived cells, which are responsible forproducing circulating blood platelets. Although comprising <0.25% of thebone marrow cells in most species, they have >10 times the volume oftypical marrow cells. See Kuter et al. Proc. Natl. Acad. Aci. USA 91:11104-11108 (1994). Megakaryocytes undergo a process known asendomitosis whereby they replicate their nuclei but fail to undergo celldivision and thereby give rise to polypoid cells. In response to adecreased platelet count, the endomitotic rate increases, higher ploidymegakaryocytes are formed, and the number of megakaryocytes may increaseup to 3-fold. See Harker J. Clin. Invest. 47: 458-465 (1968). Incontrast, in response to an elevated platelet count, the endomitoticrate decreases, lower ploidy megakaryocytes are formed, and the numberof megakaryocytes may decrease by 50%.

The exact physiological feedback mechanism by which the mass ofcirculating platelets regulates the endomitotic rate and number of bonemarrow megakaryocytes is not known. The circulating thrombopoieticfactor involved in mediating this feedback loop is now thought to bethrombopoietin (TPO). More specifically, TPO has been shown to be themain humoral regulator in situations involving thrombocytopenia. See,e.g., Metcalf Nature 369:519-520 (1994). TPO has been shown in severalstudies to increase platelet counts, increase platelet size, andincrease isotope incorporation into platelets of recipient animals.Specifically, TPO is thought to affect megakaryocytopoiesis in severalways: (1) it produces increases in megakaryocyte size and number; (2) itproduces an increase in DNA content, in the form of polyploidy, inmegakaryocytes; (3) it increases megakaryocyte endomitosis; (4) itproduces increased maturation of megakaryocytes; and (5) it produces anincrease in the percentage of precursor cells, in the form of smallacetylcholinesterase-positive cells, in the bone marrow.

Because platelets (thrombocytes) are necessary for blood clotting andwhen their numbers are very low a patient is at risk of death fromcatastrophic hemorrhage, TPO has potential useful application in boththe diagnosis and the treatment of various hematological disorders, forexample, diseases primarily due to platelet defects. Ongoing clinicaltrials with TPO have indicated that TPO can be administered safely topatients. In addition, recent studies have provided a basis for theprojection of efficacy of TPO therapy in the treatment ofthrombocytopenia, and particularly thrombocytopenia resulting fromchemotherapy, radiation therapy, or bone marrow transplantation astreatment for cancer or lymphoma. See e.g., McDonald (1992) Am. J. Ped.Hematology/Oncology 14: 8-21 (1992).

The gene encoding TPO has been cloned and characterized. See Kuter etal., Proc. Natl. Acad. Sci. USA 91: 11104-11108 (1994); Barley et al.,Cell 77: 1117-1124 (1994); Kaushansky et al., Nature 369:568-571 (1994);Wendling et al., Nature 369: 571-574 (1994); and Sauvage et al., Nature369: 533-538 (1994). Thrombopoietin is a glycoprotein with two distinctregions separated by a potential Arg—Arg cleavage site. Theamino-terminal region is highly conserved in man and mouse, and has somehomology with erythropoietin and interferon-alpha and interferon-beta.The carboxy-terminal region shows wide species divergence.

The DNA sequences and encoded peptide sequences for human TPO receptor(TPO-R; also known as c-mpl) have been described. See, Vigon et al.Proc. Natl. Acad. Sci. USA 89: 5640-5644 (1992). TPO-R is a member ofthe haematopoietin growth factor receptor family, a family characterizedby a common structural design of the extracellular domain, including forconserved C residues in the N-terminal portion and a WSXWS motif closeto the transmembrane region. See Bazan Proc. Natl. Acad. Sci. USA 87:6934-6938 (1990). Evidence that this receptor plays a functional role inhematopoiesis includes observations that its expression is restricted tospleen, bone marrow, or fetal liver in mice (see Souyri et al. Cell 63:1137-1147 (1990)) and to megakaryocytes, platelets, and CD34⁺ cells inhumans (see Methia et al. Blood 82: 1395-1401 (1993)). Further evidencefor TPO-R as a key regulator of megakaryopoiesis is the fact thatexposure of CD34⁺ cells to synthetic oligonucleotides antisense to TPO-RRNA significantly inhibits the appearance of megakaryocyte colonieswithout affecting erythroid or myeloid colony formation. Some workerspostulate that the receptor functions as a homodimer, similar to thesituation with the receptors for G-CSF and erythropoietin.

The slow recovery of platelet levels in patients suffering fromthrombocytopenia is a serious problem, and has lent urgency to thesearch for a blood growth factor agonist able to accelerate plateletregeneration.

It would be desirable to provide compounds which allow for the treatmentof thrombocytopenia by acting as a TPO mimetic.

As disclosed herein it has unexpectedly been discovered that certainhydroxy-1-azo-naphthalene derivatives are effective as agonists of theTPO receptor, they are potent TPO mimetics.

SUMMARY OF THE INVENTION

This invention relates to compounds of Formula (I):

wherein:

R, R¹, R², R³, R⁴, R⁵ and R¹¹ are each independently selected fromhydrogen, —C(O)OR⁶, —CONR⁹R¹⁰, phosphonic acid, phosphinic acid,C₁₋₆alkyl, C₁₋₆alkoxy, —(CH₂)_(p)OR⁶, nitro, cyano, halogen, —NR⁹R¹⁰,N-acylamino, N-sulfonylamino, —S(O)_(n)R⁶, C₅-C₁₂aryl, substitutedC₅-C₁₂aryl, alkyl, cycloalkyl, substituted cycloalkyl, protected —OH,and alkyl substituted with one or more substituents selected from thegroup consisting of: alkoxy, acyloxy, C₅-C₁₂aryl, substitutedC₅-C₁₂aryl, —NR⁹R¹⁰, N-acylamino, oxo, hydroxy, cycloalkyl, substitutedcycloalkyl, —C(O)OR⁶, —C(O)NR⁹R¹⁰, —S(O)₂NR⁹R¹⁰, —S(O)_(n)R⁶, aryloxy,nitro, cyano, halogen, and protected —OH; where

n is 0-3;

p is 0-6;

R⁶ is selected from hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substitutedalkyl, substituted cycloalkyl and substituted C₆-C₁₂aryl; and

R⁹ and R¹⁰ are independently selected from hydrogen, cycloalkyl,C₆-C₁₂aryl, substituted cycloalkyl, substituted C₆-C₁₂aryl, alkyl oralkyl substituted with one or more substituents selected from the groupconsisting of: alkoxy, acyloxy, aryloxy, —NR⁶R⁶, N-acylamino, oxo,hydroxy, —C(O)OR⁶, —S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro, cyano,cycloalkyl, substituted cycloalkyl, C₅-C₁₂aryl, substituted C₅-C₁₂aryland protected —OH where n and R⁶ are as described above; or R⁹ and R¹⁰taken together with the nitrogen to which they are attached represent a5 to 6 member saturated ring containing up to one other heteroatomselected from oxygen and nitrogen;

m is 0-6; and

R¹² is a cyclic or polycyclic aromatic ring containing from 3 to 16carbon atoms, optionally containing one or more heteroatoms, providedthat when the number of carbon atoms is 3 the aromatic ring contains atleast two heteroatoms and when the number of carbon atoms is 4 thearomatic ring at least one heteroatom, and optionally substituted withone or more substituents selected from the group consisting of: alkyl,cycloalkyl, substituted cycloalkyl, C₅-C₁₂aryl, substituted C₅-C₁₂aryl,aryloxy, alkoxy, acyloxy, amino, nitro, cyano, halogen, hydroxy,protected —OH, and alkyl substituted with one or more substituentsselected from the group consisting of: alkoxy, acyloxy, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, cycloalkyl, substituted cycloalkyl, aryloxy,amino, nitro, cyano, halogen, hydroxy, and protected —OH; and

pharmaceutically acceptable salts, hydrates, solvates and estersthereof;

provided that:

at least one of R, R¹, R², R³, R⁴, R⁵ or R¹¹ is selected from: sulfonicacid, —C(O)OR⁶, —CONR⁹R¹⁰, phosphonic acid and phosphinic acid; whereR⁶, R⁹ and R¹⁰ are as described above; and

provided that:

when R is sulfonic acid, R¹² does not equal unsubstituted phenyl or4-methylphenyl.

This invention relates to a method of treating thrombocytopenia, whichcomprises administering to a subject in need thereof an effective amountof a TPO mimetic compound of Formula (II):

wherein:

R, R¹, R², R³, R⁴ and R⁵ are each independently selected from hydrogen,—C(O)OR⁶, —CONR⁹R¹⁰, —SO₂NR⁹R¹⁰, phosphonic acid, phosphinic acid,C₁₋₆alkyl, C₁₋₆alkoxy, —(CH₂)_(p)OR⁶, nitro, cyano, halogen, —NR⁹R¹⁰,N-acylamino, N-sulfonylamino, —S(O)_(n)R⁶, C₅-C₁₂aryl, substitutedC₅-C₁₂aryl, alkyl, cycloalkyl, substituted cycloalkyl, protected —OH,and alkyl substituted with one or more substituents selected from thegroup consisting of: alkoxy, acyloxy, C₅-C₁₂aryl, substitutedC₅-C₁₂aryl, —NR⁹R¹⁰, N-acylamino, oxo, hydroxy, cycloalkyl, substitutedcycloalkyl, —C(O)OR⁶, —C(O)NR⁹R¹⁰, —S(O)₂NR⁹R¹⁰, —S(O)_(n)R⁶, aryloxy,nitro, cyano, halogen, and protected —OH; where

n is 0 to 3;

p is 0-6;

R⁶ is selected from hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substitutedalkyl, substituted cycloalkyl and substituted C₆-C₁₂aryl, and

R⁹ and R¹⁰ are independently selected from hydrogen, cycloalkyl,C₆-C₁₂aryl, substituted cycloalkyl, substituted C₆-C₁₂aryl, alkyl oralkyl substituted with one or more substituents selected from the groupconsisting of: alkoxy, acyloxy, aryloxy, —NR⁶R⁶, N-acylamino, oxo,hydroxy, —C(O)OR⁶, —S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro, cyano,halogen, cycloalkyl, substituted cycloalkyl, C₅-C₁₂aryl, substitutedC₅-C₁₂aryl and protected —OH where n and R⁶ are as described above; orR⁹ and R¹⁰ taken together with the nitrogen to which they are attachedrepresent a 5 to 6 member saturated ring containing up to one otherheteroatom selected from oxygen and nitrogen;

m is 0-6; and

AR is a cyclic or polycyclic aromatic ring containing from 3 to 16carbon atoms, optionally containing one or more heteroatoms, providedthat when the number of carbon atoms is 3 the aromatic ring contains atleast two heteroatoms and when the number of carbon atoms is 4 thearomatic ring at least one heteroatom, optionally substituted with oneor more substituents selected from the group consisting of: alkyl,cycloalkyl, substituted cycloalkyl, C₅-C₁₂aryl, substituted C₅-C₁₂aryl,aryloxy, hydroxy, alkoxy, acyloxy, —NR⁷R⁸, N-acylamino, N-sulfonylamino,nitro, cyano, halogen, —C(O)OR⁶, —C(O)NR⁷R⁸, —S(O)₂NR⁷R⁸, —S(O)_(n)R⁶,protected —OH, and alkyl substituted with one or more substituentsselected from the group consisting of: alkoxy, acyloxy, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, —NR⁶R⁶, N-acylamino, oxo, hydroxy, cycloalkyl,substituted cycloalkyl, —C(O)OR⁶, —C(O)NR⁷R⁸, —S(O)₂NR⁷R⁸, —S(O)_(n)R⁶,aryloxy, nitro, cyano, halogen, and protected —OH; where

n is 0 to 3;

R⁶ is selected from hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substitutedalkyl, substituted cycloalkyl and substituted C₆-C₁₂aryl; and

R⁷ and R⁸ are independently hydrogen, cycloalkyl, C₆-C₁₂aryl,substituted cycloalkyl, substituted C₆-C₁₂aryl, alkyl or alkylsubstituted with one or more substituents selected from the groupconsisting of: alkoxy, acyloxy, aryloxy, —NR⁶R⁶, N-acylamino, oxo,hydroxy, —C(O)OR⁶, —S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro, cyano,cycloalkyl, substituted cycloalkyl, halogen, C₆-C₁₂aryl, substitutedC₆-C₁₂aryl and protected —OH where n and R⁶ are as described above; and

pharmaceutically acceptable salts, hydrates, solvates and estersthereof.

The present invention also relates to the discovery that the compoundsof Formula (II) are active as agonists of the TPO receptor.

In a further aspect of the invention there is provided novel processesand novel intermediates useful in preparing the presently invented TPOmimetic compounds.

Included in the present invention are pharmaceutical compositionscomprising a pharmaceutical carrier and compounds useful in the methodsof the invention.

Also included in the present invention are methods of co-administeringthe presently invented TPO mimetic compounds with further activeingredients.

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to compounds of Formula (I) as described above.

Preferred among the presently invented Formula (I) compounds are thosein which R is not hydrogen.

Preferred among the presently invented Formula (I) compounds are thosein which R¹, R², R³, R⁴ and R⁵ are each independently selected fromhydrogen, C₁₋₆alkyl, C₁₋₆alkoxy, —(CH₂)_(p)OR⁶, —C(O)OR⁶, nitro, cyano,halogen, C₅-C₁₂aryl, —S(O)_(n)R⁶, cycloalkyl and protected —OH,

where p is 0-6,

R⁶ is selected from hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substitutedalkyl, substituted cycloalkyl and substituted C₆-C₁₂aryl, and

n is 0-3.

Preferred among the presently invented Formula (I) compounds are thosein which R is carboxylic acid or sulfonic acid; R¹, R², R³, R⁴ and R⁵are each independently selected from hydrogen, C₁₋₆alkoxy, nitro,C₁₋₆alkyl, hydroxy and halogen; m is 0; and R¹² is a cyclic orpolycyclic aromatic ring containing from 3 to 14 carbon atoms,optionally containing one or more heteroatoms, provided that when thenumber of carbon atoms is 3 the aromatic ring contains at least twoheteroatoms and when the number of carbon atoms is 4 the aromatic ringat least one heteroatom, and optionally substituted with one or moresubstituents selected from the group consisting of: alkyl, C₆-C₁₂aryl,substituted cycloalkyl, substituted C₆-C₁₂aryl, aryloxy, alkoxy,trifluoromethyl, cycloalkyl, nitro, cyano, hydroxy, substituted alkyl,halogen and protected —OH; and pharmaceutically acceptable salts,hydrates, solvates and esters thereof.

Particularly preferred among the presently invented Formula (I)compounds are those in which R is carboxylic acid or sulfonic acid; R¹,R², R³, R⁴ and R⁵ are each independently selected from hydrogen,C₁₋₆alkoxy, C₁₋₆alkyl and halogen; m is 0; and R¹² is phenyl substitutedwith one or more substituents selected from the group consisting of:alkyl, substituted alkyl, C₆-C₁₂ aryl, substituted C₆-C₁₂aryl, aryloxy,alkoxy, trifluoromethyl, halogen, hydroxy and protected —OH; andpharmaceutically acceptable salts, hydrates, solvates and estersthereof.

The most preferred among the presently invented Formula (I) compoundsare those in which R is carboxylic acid or sulfonic acid; R¹, R², R³, R⁴and R⁵ are each independently selected from hydrogen, C₁₋₆alkoxy,C₁₋₆alkyl and halogen; m is 0; and R¹² is phenyl substituted with fromone to three substituents selected from the group consisting of: alkyl,C₆-C₁₂ aryl, substituted C₆-C₁₂aryl, hydroxy, alkoxy, trifluoromethyland halogen; and pharmaceutically acceptable salts, hydrates, solvatesand esters thereof.

Preferred among the presently invented compounds are:

4-{[1-(4-chlorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-{[(3-chlorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenecarboxylicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenecarboxylicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-nitrophenyl)-1H-pyrazolyl-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[3-tert-butyl-5-hydroxy-1-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-{[3-tert-butyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-[(5-hydroxy-3-methyl-1-pyridin-2-yl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid;

4-{[1-(4-benzyloxyphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[1-(4-fluorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-1-(4-iodophenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(2-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[1-(3,4-dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[3-tert-butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-napthalenecarboxylicacid;

Methyl5-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazo-4-yl]azo}-6-hydroxy-2-napthalenecarboxylate;

1-{[1-(3,4Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-2-hydroxynaphthalene;and

4-[(1-Benzyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid.

This invention also relates to Compounds of Formula (II), as describedabove, which are included in the pharmaceutical compositions of theinvention and used in the methods of the invention.

Preferred among the presently invented Formula II compounds are those inwhich R is not hydrogen.

Preferred among the presently invented Formula II compounds are those inwhich R¹, R², R³, R⁴ and R⁵ are each independently selected fromhydrogen, C₁₋₆alkyl, C₁₋₆alkoxy, —(CH₂)_(p)OR⁶, —C(O)OR⁶, nitro, cyano,halogen, C₅-C₁₂aryl, S(O)_(n)R⁶, cycloalkyl and protected —OH,

where p is 0-6,

R⁶ is selected from hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substitutedalkyl, substituted cycloalkyl and substituted C₆-C₁₂aryl, and

n is 0-3.

Preferred among the presently invented Formula II compounds are those inwhich R is carboxylic acid or sulfonic acid; R¹, R², R³, R⁴ and R⁵ areeach independently selected from hydrogen, C₁₋₆alkoxy, nitro, C₁₋₆alkyland halogen; m is 0; and AR is cyclic or polycyclic aromatic C₃-C₁₄,optionally containing from one to three heteroatoms, provided that whenC is 3 the aromatic ring contains at least two heteroatoms and when C is4 the aromatic ring contains at least one heteroatom, and optionallysubstituted with one or more substituents selected from the groupconsisting of: alkyl, C₆-C₁₂ aryl, substituted cycloalkyl, substitutedC₆-C₁₂aryl, aryloxy, hydroxy, alkoxy, cycloalkyl, amino, nitro, cyano,halogen and protected —OH; and pharmaceutically acceptable salts,hydrates, solvates and esters thereof.

Also preferred among the presently invented Formula II compounds arethose in which R is carboxylic acid or sulfonic acid; R¹, R², R³, R⁴ andR⁵ are each independently selected from hydrogen, C₁₋₆alkoxy, C₁₋₆alkyland halogen; m is 0; and AR is cyclic or polycyclic aromatic C₃-C₁₄,optionally containing from one to three heteroatoms, provided that whenC is 3 the aromatic ring contains at least two heteroatoms and when C is4 the aromatic ring contains at least one heteroatom, and optionallysubstituted with one or more substituents selected from the groupconsisting of: alkyl, C₆-C₁₂ aryl, substituted C₆-C₁₂aryl, aryloxy,hydroxy, alkoxy, amino, halogen and protected —OH; and pharmaceuticallyacceptable salts, hydrates, solvates and esters thereof.

Also preferred among the presently invented Formula II compounds arethose in which R is carboxylic acid or sulfonic acid; R¹, R², R³, R⁴ andR⁵ are each independently selected from hydrogen, C₁₋₆alkoxy, C₁₋₆alkyland halogen; m is 0; and AR is selected from naphthalene, phenyl andpyrazole, and optionally substituted with from one to three substituentsselected from the group consisting of: alkyl, C₆-C₁₂ aryl, substitutedC₆-C₁₂aryl, hydroxy, alkoxy, hydroxy and halogen; and pharmaceuticallyacceptable salts, hydrates, solvates and esters thereof.

Preferred among the compounds of Formula II are those in which R iscarboxylic acid or sulfonic acid; R¹, R², R³, R⁴ and R⁵ are eachindependently selected from hydrogen, C₁₋₆alkoxy, nitro, C₁₋₆alkyl andhalogen; m is 0; and AR is a cyclic or polycyclic aromatic ringcontaining from 3 to 14 carbon atoms, optionally containing one or moreheteroatoms, provided that when the number of carbon atoms is 3 thearomatic ring contains at least two heteroatoms and when the number ofcarbon atoms is 4 the aromatic ring at least one heteroatom, andoptionally substituted with one or more substituents selected from thegroup consisting of: alkyl, C₆-C₁₂ aryl, substituted cycloalkyl,substituted C₆-C₁₂aryl, aryloxy, hydroxy, alkoxy, cycloalkyl,trifluoromethyl, amino, nitro, cyano, halogen, hydroxy and protected—OH; and pharmaceutically acceptable salts, hydrates, solvates andesters thereof.

Particularly preferred among the compounds of Formula II are those inwhich R is carboxylic acid or sulfonic acid; R¹, R², R³, R⁴ and R⁵ areeach independently selected from hydrogen, C₁₋₆alkoxy, C₁₋₆alkyl andhalogen; m is 0; and AR is a cyclic or polycyclic aromatic ringcontaining from 3 to 14 carbon atoms, optionally containing one or moreheteroatoms, provided that when the number of carbon atoms is 3 thearomatic ring contains at least two heteroatoms and when the number ofcarbon atoms is 4 the aromatic ring at least one heteroatom, andoptionally substituted with one or more substituents selected from thegroup consisting of: alkyl, C₆-C₁₂ aryl, substituted C₆-C₁₂aryl,aryloxy, hydroxy, alkoxy, amino, trifluoromethyl, halogen, hydroxy andprotected —OH; and pharmaceutically acceptable salts, hydrates, solvatesand esters thereof.

The most preferred among the compounds of Formula II are those in whichR is carboxylic acid or sulfonic acid; R¹, R², R³, R⁴ and R⁵ are eachindependently selected from hydrogen, C₁₋₆alkoxy, C₁₋₆alkyl and halogen;m is 0; and AR is selected from naphthalene, phenyl and pyrazole, andoptionally substituted with from one to three substituents selected fromthe group consisting of: alkyl, C₆-C₁₂ aryl, substituted C₆-C₁₂aryl,hydroxy, alkoxy, trifluoromethyl and halogen; and pharmaceuticallyacceptable salts, hydrates, solvates and esters thereof.

Preferred among the compounds of Formula II are:

3-hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid;

3-hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid;

3-hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo]-1-naphthalenesulfonic acid;

3-hydroxy-4-[(2-hydroxy-5-methyl-1-phenyl)azo]-1-naphthalenesulfonicacid;

3-hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-1-naphthalenesulfonic acid;

3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid;

3-hydroxy-4-[(10-hydroxy-9-phenanthrenyl)azo]-1-naphthalenesulfonicacid;

3-hydroxy-4-[(2-hydroxy-7-methoxy-1-naphthalenyl)azo]-1-naphthalenesulfonicacid;

3-hydroxy-4-[(4-hydroxy-2-methoxy-1-naphthalenyl)azo]-1-naphthalenesulfonicacid;

4-[(1,3-dimethyl-5-hydroxy-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-1-(4-methylphenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[1-(4-chlorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-{[(3-chlorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenecarboxylicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenecarboxylicacid;

4-{1-[3-(N-ethylsulfonamidophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-[(3-ethoxycarbonyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[3-tert-butyl-5-hydroxy-1-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-[(3-ethoxy-5-hydroxy-1-(4-nitrophenyl)-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;

4-{[3-tert-butyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-[(5-hydroxy-3-methyl-1-pyridin-2-yl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid;

4-{[1-(4-benzyloxyphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[1-(4-fluorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-1-(4-iodophenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(2-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[1-(3,4-dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;

4-{[3-tert-butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;

4-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-napthalenecarboxylicacid;

Methyl5-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-6-hydroxy-2-napthalenecarboxylate;

1-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-2-hydroxynaphthalene;

3-Hydroxy-4-({5-hydroxy-1-[(4-methanesulfonyl)phenyl]-3-methyl-1H-pyrazol-4-yl}azo)-1-naphthalenesulfonicacid;

4-[(1-Benzyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;

4-({1-[4-(Aminosulfonyl)phenyl]-5-hydroxy-3-methyl-1H-pyrazol-4-yl}azo)-3-hydroxy-1-naphthalenesulfonicacid; and

4-[(1-tert-Butyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid.

By the term “protected hydroxy” or “protected —OH” as used herein, ismeant the alcoholic or carboxylic—OH groups which can be protected byconventional blocking groups in the art as described in “ProtectiveGroups In Organic Synthesis” by Theodora W. Greene, Wiley-Interscience,1981, New York. Compounds containing protected hydroxy groups may alsobe useful as intermediates in the preparation of the pharmaceuticallyactive compounds of the invention.

By the term “C₅-C₁₂ aryl” as used herein, unless otherwise defined, ismeant a cyclic or polycyclic aromatic C₅-C₁₂ optionally containing oneor two heteroatoms.

By the term “C₆-C₁₂ aryl” as used herein, unless otherwise defined, ismeant phenyl, naphthyl, 3,4-methylenedioxyphenyl, pyridyl, or biphenyl.

By the term “substituted” as used herein, unless otherwise defined, ismeant that the subject chemical moiety has one or more substituentsselected from the group consisting of: hydroxyalkyl, alkoxy, acyloxy,alkyl, amino, N-acylamino, hydroxy, —(CH₂)_(g)C(O)OR⁶, —S(O)_(n)R⁷,nitro, cyano, halogen, trifluoromethyl and protected —OH, where g is0-6, R⁶ is hydrogen or alkyl, n is 0-2, and R⁷ is hydrogen or alkyl.

By the term “alkoxy” as used herein is meant —Oalkyl where alkyl is asdescribed herein including —OCH₃ and —OC(CH₃)₂CH₃.

The term “cycloalkyl” as used herein unless otherwise defined, is meanta nonaromatic, unsaturated or saturated, cyclic or polycyclic C₃-C₁₂.

Examples of cycloalkyl and substituted cycloalkyl substituents as usedherein include: cyclohexyl, 4-hydroxy-cyclohexyl, 2-ethylcyclohexyl,propyl 4-methoxycyclohexyl, 4-methoxycyclohexyl, 4-carboxycyclohexyl andcyclopentyl.

By the term “acyloxy” as used herein is meant —OC(O)alkyl where alkyl isas described herein. Examples of acyloxy substituents as used hereininclude: —OC(O)CH₃, —OC(O)CH(CH₃)₂ and —OC(O)(CH₂)₃CH₃.

By the term “N-acylamino” as used herein is meant —N(H)C(O)alkyl, wherealkyl is as described herein. Examples of N-acylamino substituents asused herein include: —N(H)C(O)CH₃, —N(H)C(O)CH(CH₃)₂ and—N(H)C(O)(CH₂)₃CH₃.

By the term “aryloxy” as used herein is meant —OC₆-C₁₂aryl whereC₆-C₁₂aryl is phenyl, naphthyl, 3,4-methylenedioxyphenyl, pyridyl orbiphenyl optionally substituted with one or more substituents selectedfrom the group consisting of: alkyl, hydroxyalkyl, alkoxy,trifuloromethyl, acyloxy, amino, N-acylamino, hydroxy,—(CH₂)_(g)C(O)OR⁶, —S(O)_(n)R⁷, nitro, cyano, halogen and protected —OH,where g is 0-6, R⁶ is hydrogen or alkyl, n is 0-2 and R⁷ is hydrogen oralkyl. Examples of aryloxy substituents as used herein include: phenoxy,4-fluorophenyloxy and biphenyloxy.

By the term “heteroatom” as used herein is meant oxygen, nitrogen orsulfur.

By the term “halogen” as used herein is meant a substituent selectedfrom bromide, iodide, chloride and fluoride.

By the term “alkyl” and derivatives thereof and in all carbon chains asused herein is meant a linear or branched, saturated or unsaturatedhydrocarbon chain having C₁-C₁₂ carbon atoms. Examples of alkylsubstituents as used herein include: —CH₃, —CH₂-CH₃, —CH₂—CH₂—CH₃,—CH(CH₃)₂, —C(CH₃)₃, —(CH₂)₃—CH₃, —CH₂—CH(CH₃)₂ and —CH(CH₃)—CH₂—CH₃,—CH═CH₂.

By the term “treating” and derivatives thereof as used herein, is meantprophylatic or therapeutic therapy.

All publications, including but not limited to patents and patentapplications, cited in this specification are herein incorporated byreference as though fully set forth.

Compounds of Formula (II) are included in the pharmaceuticalcompositions of the invention and used in the methods of the invention.Where a —COOH or —OH group is present, pharmaceutically acceptableesters can be employed, for example methyl, ethyl, pivaloyloxymethyl,and the like for —COOH, and acetate maleate and the like for —OH, andthose esters known in the art for modifying solubility or hydrolysischaracteristics for use as sustained release or prodrug formulations.

The compounds of Formula II are prepared as shown in Schemes I to IIIbelow wherein R, R¹, R², R³, R⁴, R⁵, m and AR are as defined in FormulaII and provided that the ‘R’, m and AR substituents do not include anysuch substituents that render inoperative the processes of Schemes I toIII. All of the starting materials are commercially available or arereadily made from commercially available starting materials by those ofskill in the art.

Scheme I outlines the formation of Formula II compounds. As used inscheme I the diazo compound (b) is prepared from the threehydroxy-1-napthalene compound (a) by treating (a) with4-benzenediazonium sulfate in the presence of an appropriate base,preferably sodium hydrogen carbonate. Reduction of compound (b) withsodium hydrogen sulfite in water yielded the4-amino-3-hydroxy-1-napthalene compound (c). Compound (c) is diazotizedby reaction with sodium nitrite and an appropriate acid, such as nitricacid, sulfuric acid or, preferably hydrochloric acid, in an appropriateaqueous solvent, such as water or, preferably an ethanol-water mixtureto produce diazonium compound (d). Compound (e) is prepared by reactingcompound (d) in a coupling reaction with an appropriate aryl species inthe presence of a base, preferably sodium hydrogen carbonate, or anacid, preferably hydrochloric acid.

Scheme II outlines the formation of pyrazoles for use in scheme I. Anamine such as 4-methylaniline, compound (f), is diazotized by the actionof sodium nitrite and an appropriate acid such as hydrochloric acid,nitric acid or sulfuric acid in an appropriate aqueous solvent systemsuch as water or ethanol-water mixtures then reduced in situ by tinchloride to afford hydrazine, compound (g). The hydrazine is thencondensed with a beta-keto ester such as ethyl acetoacetate, compound(h), in an appropriate solvent such as acetic acid or ethanol at anappropriate temperature typically 0-100° to give the correspondingpyrazole, compound (I) as described herein.

Scheme III outlines an alternative preparation of compounds of FormulaII. A pyrazole (j) prepared by the method of Scheme II is treated with asulfonyl azide such as p-toluenesulfonyl azide in the presence of a basetypically triethylamine or pyridine in a suitable solvent such asethanol, methanol or tetrahydrofuran to afford diazopyrazole (k).Compound (I) is then formed by the reaction of compound (k) in acoupling reaction with an appropriate aryl species such as naphthalenecompound (a) from Scheme I in the presence of a base, typicallytriethylamine or sodium hydrogen carbonate, or an acid, preferablyhydrochloric acid.

The treatment of thrombocytopenia, as described herein, is accomplishedby enhancing the production of platelets.

By the term “co-administering” and derivatives thereof as used herein ismeant either simultaneous administration or any manner of separatesequential administration of a TPO mimetic compound, as describedherein, and a further active ingredient or ingredients, known to treatthrombocytopenia, including chemotherapy-induced thrombocytopenia andbone marrow transplantation and other conditions with depressed plateletproduction. Preferably, if the administration is not simultaneous, thecompounds are administered in a close time proximity to each other.Furthermore, it does not matter if the compounds are administered in thesame dosage form, e.g. one compound may be administered topically andanother compound may be administered orally.

Because the pharmaceutically active compounds of the present inventionare active as TPO mimetics they exhibit therapeutic utility in treatingthrombocytopenia and other conditions with depressed plateletproduction.

In determining potency as TPO mimetics, the following assays wereemployed:

Luciferase Assay

Compounds of the present invention were tested for potency as mimeticsof the TPO receptor in a Luciferase assay such as described in Lamb, etal., Nucleic Acids Research 23: 3283-3289 (1995) and Seidel, et al.,Proc. Natl. Acad. Sci., USA 92: 3041-3045 (1995) by substituting aTPO-responsive BaF3 cell line (Vigon et al. Proc. Natl. Acad. Sci. USA1992, 89, 5640-5644) for the HepG2 cells utilized therein. The murineBaF3 cells express TPO receptors and closely match the pattern of STAT(signal transducers and activators of transcription) activation observedin primary murine and human bone marrow cells in response to TPO.

Some of the most preferred compounds of this invention were also activein an in vitro proliferation assay using the murine 32D-mpl cell line(Bartley, T. D. et al., Cell, 1994, 77, 1117-1124). 32D-mpl cellsexpress Tpo-R and their survival is dependent on the presence of TPO.Likewise, some of the most preferred compounds of this invention werealso positive in stimulating the maturation of megakaryocytes from humanbone marrow cells. In this assay, purified human CD34+ progenitor cellswere incubated in liquid culture with test compounds for 10 days and thenumber of cells expressing the transmembrane glycoprotein CD41 (gpIIb),a megakaryocytic marker, was then measured by flow cytometry (seeCwirla, S. E. et al Science, 1997, 276, 1696-1699).

The pharmaceutically active compounds within the scope of this inventionare useful as TPO mimetics in mammals, including humans, in needthereof.

Some of the preferred compounds within the scope of the invention showedactivation from about 4% to 130% of control (control is the maximalresponse to TPO) at a concentration of 0.01-10 uM in the luciferaseassay. The preferred compounds of the invention also promoted theproliferation of 32D-mpl cells at a concentration of 0.01 to 100 uM. Thepreferred compounds of the invention also showed activity in the CD41megakaryocytic assay at a concentration of 0.01 to 30 uM.

The present invention therefor provides a method of treatingthrombocytopenia and other conditions with depressed plateletproduction, which comprises administering a compound of Formula (II), asdescribed above, in a quantity effective to enhance platelet production.The compounds of Formula (II) also provide for a method of treating theabove indicated disease states because of their demonstrated ability toact as TPO mimetics. The drug may be administered to a patient in needthereof by any conventional route of administration, including, but notlimited to, intravenous, intramuscular, oral, subcutaneous, intradermal,and parenteral.

The pharmaceutically active compounds of the present invention areincorporated into convenient dosage forms such as capsules, tablets, orinjectable preparations. Solid or liquid pharmaceutical carriers areemployed. Solid carriers include, starch, lactose, calcium sulfatedihydrate, terra alba, sucrose, talc, gelatin, agar, pectin, acacia,magnesium stearate, and stearic acid. Liquid carriers include syrup,peanut oil, olive oil, saline, and water. Similarly, the carrier ordiluent may include any prolonged release material, such as glycerylmonostearate or glyceryl distearate, alone or with a wax. The amount ofsolid carrier varies widely but, preferably, will be from about 25 mg toabout 1 g per dosage unit. When a liquid carrier is used, thepreparation will be in the form of a syrup, elixir, emulsion, softgelatin capsule, sterile injectable liquid such as an ampoule, or anaqueous or nonaqueous liquid suspension.

The pharmaceutical preparations are made following conventionaltechniques of a pharmaceutical chemist involving mixing, granulating,and compressing, when necessary, for tablet forms, or mixing, fillingand dissolving the ingredients, as appropriate, to give the desired oralor parenteral products.

Doses of the presently invented pharmaceutically active compounds in apharmaceutical dosage unit as described above will be an efficacious,nontoxic quantity preferably selected from the range of 0.001-100 mg/kgof active compound, preferably 0.001-50 mg/kg. When treating a humanpatient in need of a TPO mimetic, the selected dose is administeredpreferably from 1-6 times daily, orally or parenterally. Preferred formsof parenteral administration include topically, rectally, transdermally,by injection and continuously by infusion. Oral dosage units for humanadministration preferably contain from 0.05 to 3500 mg of activecompound. Oral administration, which uses lower dosages is preferred.Parenteral administration, at high dosages, however, also can be usedwhen safe and convenient for the patient.

Optimal dosages to be administered may be readily determined by thoseskilled in the art, and will vary with the particular TPO mimetic inuse, the strength of the preparation, the mode of administration, andthe advancement of the disease condition. Additional factors dependingon the particular patient being treated will result in a need to adjustdosages, including patient age, weight, diet, and time ofadministration.

The method of this invention of inducing TPO mimetic activity inmammals, including humans, comprises administering to a subject in needof such activity an effective TPO mimetic amount of a pharmaceuticallyactive compound of the present invention.

The invention also provides for the use of a compound of Formula (II) inthe manufacture of a medicament for use as a TPO mimetic.

The invention also provides for the use of a compound of Formula (II) inthe manufacture of a medicament for use in therapy.

The invention also provides for the use of a compound of Formula (II) inthe manufacture of a medicament for use in enhancing plateletproduction.

The invention also provides for the use of a compound of Formula (II) inthe manufacture of a medicament for use in treating thrombocytopenia.

The invention also provides for a pharmaceutical composition for use asa TPO mimetic which comprises a compound of Formula (II) and apharmaceutically acceptable carrier.

The invention also provides for a pharmaceutical composition for use inthe treatment of thrombocytopenia which comprises a compound of Formula(II) and a pharmaceutically acceptable carrier.

The invention also provides for a pharmaceutical composition for use inenhancing platelet production which comprises a compound of Formula (II)and a pharmaceutically acceptable carrier.

No unacceptable toxicological effects are expected when compounds of theinvention are administered in accordance with the present invention.

In addition, the pharmaceutically active compounds of the presentinvention can be co-administered with further active ingredients, suchas other compounds known to treat thrombocytopenia, includingchemotherapy-induced thrombocytopenia and bone marrow transplantationand other conditions with depressed platelet production, or compoundsknown to have utility when used in combination with a TPO mimetic.

Contemplated Equivalents

It will be appreciated by the person of ordinary skill in the art thatthe compounds of Formula I and II may also exist in tautomeric forms,wherein the double bond that is drawn between the two nitrogen atomsexists between the lower nitrogen atom and the AR substituent.Tautomeric forms of the compounds of Formula I and II are exemplified bythe following Formula III

where the ‘R’ groups are as defined above. All such compounds areincluded in the scope of the invention and inherently included in thedefinition of the compounds of formulas I and II.

Without further elaboration, it is believed that one skilled in the artcan, using the preceding description, utilize the present invention toits fullest extent. The following Examples are, therefore, to beconstrued as merely illustrative and not a limitation of the scope ofthe present invention in any way.

EXPERIMENTAL DETAILS EXAMPLE 1 Preparation of3-hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo]-1-naphthalenesulfonic acid

To a stirring solution of 1-diazo-2-naphthol-4-sulfonic acid (1.49 g,5.95 mmol) and 2-naphthol (0.858 g, 5.95 mmol) in water (20 mL), sodiumbicarbonate (1.50 g, 17.85 mmol) was added slowly. The resultingsolution was heated at 60° C. with stirring overnight. The solution wascooled to room temperature, and was adjusted to pH=1 with 3 Nhydrochloride solution. The purple precipitate was isolated byfiltration and washed with water to provide the title compound (1.35 g,58%) MS(ES) m/z 393 [M−H].

EXAMPLE 2 Preparation of3-hydroxy-4-[(10-hydroxy-9-phenanthrenyl)azo]-1-naphthalenesulfonic acid

Following the procedure of Example 1, except substituting 9-phenathrolfor 2-naphthol, the title compound was prepared as a black solid (0.048g, 16%). MS(ES) m/z 442. [M−H].

EXAMPLE 3 Preparation of3-hydroxy-4-[(2-hydroxy-7-methoxy-1-naphthalenyl)azo]1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting7-methoxy-2-naphthol for 2-naphthol, the title compound was prepared asa black solid (2.66 g, 74%). MS(ES) m/z 423 [M−H].

EXAMPLE 4 Preparation of3-hydroxy-4-[(4-hydroxy-2-methoxy-1-naphthalenyl)azo]-1-naphthalenesulfonicacid

a) 3-methoxy-1-naphthol

To a stirring solution of 1,3-dihydroxynaphthalene (2.31 g, 14.4 mmol)in methanol (150 mL) at 0° C., hydrochloride gas was bubbed for 10 min.The resulting solution was continued stirring at room temperature for 24hrs. A residue was obtained after evaporation of methanol and purifiedby silica gel column chromatography eluted with chloroform to providethe title compound as purple crystals (1.42 g, 57%). ¹H NMR(300 MHzCDCl3) δ8.08(d, 1H), 7.70(d, 1H), 7.46(t, 1H), 7.34(t, 1H), 6.78 (s,1H), 6.54 (s, 1H), 5.61(s, 1H), 3.90(s, 3H).

b)3-Hydroxy-[4-(4-hydroxy-2-methoxy-1-naphthalenyl)azo]-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting3-methoxy-1-naphthol for 2-naphthol, the title compound was prepared asa black solid (2.37 g, 88%). MS(ES) m/z 423 [M−H].

EXAMPLE 53-Hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid

The title compound is commercially available from Pfaltz and Bauer,Waterbury, Conn. and used as provided. MS(ES) m/z 438 [M−H].

EXAMPLE 63-Hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid, monosodium salt

The title compound is commercially available from the Aldrich ChemicalCompany, Milwaukee, Wis. and used as provided. MS(ES) m/z 438 [M−H].

EXAMPLE 73-Hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-1-naphthalenesulfonic acid

The title compound is commercially available from Aldrich ChemicalCompany, Milwaukee, Wis. and used as provided. MS(ES) m/z 393 [M−H].

EXAMPLE 83-Hydroxy-4-[(2-hydroxy-5-methyl-1-phenyl)azo]-1-naphthalenesulfonicacid

The title compound is commercially available Aldrich Chemical Company,Milwaukee, Wis. and used as provided. MS(ES) m/z 357 [M−H].

EXAMPLE 9 Preparation of3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid, monosodium salt

Following the procedure of Example 1, except substituting3-methyl-1-phenyl-3-pyrazolin-5-one for 2-naphthol, the title compoundwas prepared as a red solid 3.82 g; 90%). MS(ES) m/z 423 [M−H].

EXAMPLE 10 Preparation of4-[(1,3-dimethyl-5-hydroxy-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid, monohydrate, monosodium salt

Following the procedure of Example 1, except substituting1,3-dimethyl-3-pyrazolin-5-one for 2-naphthol, the title compound wasprepared as a red solid 1.95 g; 49%). Anal (C₁₅H₁₄N₄OS.Na.H₂O) calcd: C,44.8; H, 4.0; N, 13.9. found: C, 44.6; H, 3.7; N, 13.7.

EXAMPLE 11 Preparation of3-hydroxy-4-{[5-hydroxy-1-(4-methylphenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting3-methyl-1-(4-methylphenyl)-3-pyrazolin-5-one for 2-naphthol, the titlecompound was prepared as a red solid (2.1 g; 81%). MS(ES) m/z 436.9[M−H].

EXAMPLE 12 Preparation of4-{[1-(4-chlorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting1-(4-chlorophenyl)-3-methyl-3-pyrazolin-5-one for 2-naphthol, the titlecompound was prepared as a red solid (1.8 g; 97%). MS(ES) m/z 456.7[M−H].

EXAMPLE 13 Preparation of4-{[(3-chlorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting1-(3-chlorophenyl)-3-methyl-3-pyrazolin-5-one for 2-naphthol, the titlecompound was prepared as a red solid (0.69 g; 50%). MS(ES) m/z 456.7[M−H].

EXAMPLE 14 Preparation of3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenecarboxylicacid

a) 3-Nitro-1-napthalenecarboxylic acid

A mixture of 3-nitro-1,8-napthalic anhydride (100 g, 0.411 mol.) andsodium hydroxide (55.8 g; 1.4 mol.) in water (2 L) was added to asuspension of mercury (I) oxide (96.8 g; 0.447 mol.) in water (270 mL)and glacial acetic acid (200 mL). The mixture which frothed vigorouslywas then stirred and heated under reflux for 3 days. The suspension wasthen hot-filtered and the insoluble residue dried in vacuo at 70° for 3days to give a yellow powder (169.7 g). This solid was suspended in amixture of concentrated hydrochloric acid (500 mL) and water (1 L) andstirred and heated under reflux for 4 h. Hot-filtration gave crude3-nitronapthalene-1-carboxylic acid (92.3 g) which was recrystallisedfrom glacial acetic acid with hot-filtration to remove some insolublematerial to afford the title compound (36.4 g) as a cream, crystallinesolid. mp 255-257°.

b) 3-Amino-1-napthalenecarboxylic acid, sodium salt

A suspension of the compound from example 14 a) (10.0 g; 0.046 mol.) inethanol (100 mL) was treated with 10% aqu. sodium hydroxide (16.6 mL;0.046 mol.) and water (20.0 mL) and stirred until all solids haddissolved. This solution was then hydrogenated over 10% w/wpalladium-on-charcoal (2.0 g) at room temperature and 50 p.s.i. for 4 h.The solution was filtered and evaporated to afford the title compound(8.65 g; 90%) as a yellow solid. MS(ES) m/z 188 [M+H].

c) 3-Hydroxy-1-napthalenecarboxylic acid

A solution of the compound from example 14 b) (8.73 g; 0.042 mol.) inwater (300 mL) was treated with 2M aqu. sulfuric acid (60.0 mL) toprecipitate the free acid as a fine powder. This suspension was thenstirred and cooled to 10° then slowly treated dropwise with a solutionof sodium nitrite (3.03 g; 0.044 mol.) in water (30.0 mL). After 30 min.at 10° the solution was added very slowly dropwise to a refluxingsolution of 40% aqu. sulfuric acid (1 L). Complete addition took ˜1 h.After complete addition the mixture was heated under reflux for afurther 15 min. then quickly hot-filtered through a plug of glass woolto remove insoluble, charred material. The filtrate was allowed to cooldepositing the title compound (5.85 g; 74%) as yellow crystals. mp210-212°. MS(ES) m/z 187 [M−H].

d) 4-Amino-3-hydroxy-1-naphthalenecarboxylic acid

To a stirred solution of p-benzenediazonium sulfonate, which wasprepared by the addition of sodium sulfanilate (0.525 g, 2.7 mmole) tosodium nitrite at 0°, and the compound from example 14 c) (0.413 g, 2.2mmol) in water (20 mL), sodium bicarbonate (2.3 g, 27.0 mmol) was addedslowly. The resulting solution was heated at 60° C. with stirringovernight. After the solution was cooled to 50° C., sodium hydrogensulfite (1.05 g, 6.0 mmole) was added. The resulting solution wasstirred for 30 min. at 50° C. After cooling down to room temperature,the solid was removed by filtration. The filtrate was evaporated todryness and the residue was purified by flash chromatography (silicagel, 45% dichloromethane/45% ethyl acetate/10% methanol) to give thetitle compound (0.066 g, 15%) MS(ES) m/z 203.8 [M+H].

e)3-Hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenecarboxylicacid

To a stirred solution of the compound from example 14 d) (0.203 g, 1.0mmol) in ethanol (1.0 ml), ice (1.0 g) and hydrochloric acid (37%, 0.3ml), was added a solution of sodium nitrite (0.083 g, 1.2 mmol) in water(0.2 ml). After the resulting solution was stirred at room temperaturefor 30 min, 3-methyl-1-phenyl-3-pyrazolin-5-one (0.174 g, 1.0 mmole) wasadded. Sodium bicarbonate (0.84 g, 10 mmole) was added slowly into thereaction mixture and the resulting solution was heated at 60° C. withstirring overnight. A red precipitate was obtained by adding 3N HClsolution which was purified by chromatography [ODS, step gradient,10-90% acetonitrile/water (0.1% TFA)] to give the title compound (0.021g, 5%) MS(ES) m/z 386.9 [M−H].

EXAMPLE 15 Preparation of3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-methylphenyl)-1H-pyrazol-4-yl]azo}-1-napthalenecarboxylicacid

Following the procedure of Example 14 e), except substituting3-methyl-1-(4-methylphenyl)-3-pyrazolin-5-one for3-methyl-1-phenyl-3-pyrazolin-5-one, the title compound was prepared asa red solid (0.004 g). MS(ES) m/z 402.6 [M−H].

EXAMPLE 16 Preparation of3-hydroxy-4-{{5-hydroxy-1-[3-(N-ethylsulfonamido)phenyl]-3-methyl-1H-pyrazol-4-yl}azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting[3-(N-ethylsulfonamido)phenyl]-3-methyl-3-pyrazolin-5-one for2-naphthol, the title compound was prepared as a red solid (). MS(ES)m/z.530 [M−H].

EXAMPLE 17 Preparation of4-[(3-ethoxycarbonyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;

Following the procedure of Example 1, except substituting3-ethoxycarbonyl-1-phenyl-3-pyrazolin-5-one for 2-naphthol, the titlecompound was prepared as a red solid (). MS(ES) m/z481 [M−H].

EXAMPLE 18 Preparation of3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting3-methyl-1-(4-nitrophenyl)-3-pyrazolin-5-one for 2-naphthol, the titlecompound was prepared as a red solid (2.0 g; 99%). MS(ES) m/z 468 [M−H].

EXAMPLE 19 Preparation of4-{[3-tert-butyl-5-hydroxy-1-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting3-tert-butyl-1-methyl-3-pyrazolin-5-one for 2-naphthol, the titlecompound was prepared as a red solid solid (1.4 g; 82%). MS(ES) m/z 403[M−H].

EXAMPLE 20 Preparation of4-[(3-ethoxy-5-hydroxy-1-(4-nitrophenyl)-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting3-ethoxy-1-(4-nitrophenyl)-3-pyrazolin-5-one for 2-naphthol, the titlecompound was prepared as a red solid (1.9 g; 89%). MS(ES) m/z 498 [M−H].

EXAMPLE 21 Preparation of4-{[3-tert-butyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting3-tert-butyl-1-phenyl-3-pyrazolin-5-one for 2-naphthol, the titlecompound was prepared as a red solid (1.1 g; 55%). MS(ES) m/z 465 [M−H].

EXAMPLE 22 Preparation of3-hydroxy-4-[(5-hydroxy-3-methyl-1-pyridin-2-yl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid,

a) 3-Methyl-1-pyridin-2-yl-3-pyrazolin-5-one

A solution of 2-hydrazinopyridine (1.35 g; 0.012 mol.) and ethylacetoacetate (1.60 mL; 0.012 mol.) in glacial acetic acid (50.0 mL) wasstirred and heated at 100° for 24 h.

The solvent was evaporated and the product purified by chromatography(silica gel, 50% ethyl acetate/hexanes) to afford the title compound(0.78 g; 37%) as a colorless solid. MS(ES) m/z 176 [M+H].

b)3-hydroxy-4-[(5-hydroxy-3-methyl-1-pyridin-2-yl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid

Following the procedure of Example 1, except the compound from Example22a) 2-naphthol, the title compound was prepared as a red solid (1.33 g;73%). MS(ES) m/z 424 [M−H].

EXAMPLE 23 Preparation of4-{[1-(4-benzyloxyphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

a) 4-Benzyloxyphenylhydrazine

A solution of 4-benzyloxyaniline hydrochloride (11.3 g; 0.048 mole) inconcentrated hydrochloric acid (40.0 mL) was cooled to 0° then treateddropwise with a solution of sodium nitrite (3.28 g; 0.048 mole) in water(20.0 mL). The mixture was stirred 0° for a further 10 min. then pouredinto a cold (−10°) solution of tin dichloride hydrate (40.0 g; 0.18mole) in concentrated hydrochloric acid (40.0 mL). The mixture wasallowed to warm to room temperature with stirring for 1 h.

The mixture was basified with 10% aqu. sodium hydroxide, ethyl acetate(1 L) was added and the mixture filtered to remove unwanted tinresidues. The organic layer was then dried and evaporated to afford thetitle compound as a yellow solid (6.9 g; 67%). mp 105-107°.

b) 1-(4-Benzyloxyphenyl)-3-methyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except the compound fromExample 23a) for 2-hydrazinopyridine, the title compound was prepared(1.6 g; 60%). MS(ES) m/z 281 [M+H].

c)4-{[1-(4-Benzyloxyphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except the compound from Example23b) for 2-naphthol, the title compound was prepared as a red solid (2.8g; 98%). MS(ES) m/z 529 [M−H].

EXAMPLE 24 Preparation of3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

a) 3-Methyl-1-(3-trifluoromethylphenyl)-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting3-trifluoromethylphenylhydrazine for 2-hydrazinopyridine, the titlecompound was prepared (0.78 g; 76%). MS(ES) m/z 243 [M+H].

b)3-Hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 24a) for 2-naphthol, the title compound was prepared as ared solid (1.19 g; 78%). MS(ES) m/z 491 [M−H].

EXAMPLE 25 Preparation of4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

a) 1-(3,4-Dimethylphenyl)-3-methyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting3,4-dimethylphenylhydrazine for 2-hydrazinopyridine, the title compoundwas prepared (16.8 g; 64%). MS(ES) m/z 203 [M+H].

b)4-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 25a) for 2-naphthol, the title compound was prepared as ared solid (23.3 g; 97%). MS(ES) m/z 451 [M−H].

EXAMPLE 26

Preparation of3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

a) 3-Methyl-1-(3-nitrophenyl)-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting3-nitrophenylhydrazine for 2-hydrazinopyridine, the title compound wasprepared (3.16 g; 98%). MS(ES) m/z 220 [M+H].

b)3-Hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 26a) for 2-naphthol, the title compound was prepared as ared solid (2.4 g; 92%). MS(ES) m/z 468 [M−H].

EXAMPLE 27 Preparation of4-{[1-(4-fluorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

a) 1-(4-Fluorophenyl)-3-methyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting4-fluorophenylhydrazine for 2-hydrazinopyridine, the title compound wasprepared (2.2 g; 75%). MS(ES) m/z 193 [M+H].

b)3-Hydroxy-4-{[1-(3-fluorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 27a) for 2-naphthol, the title compound was prepared as ared solid (2.03 g; 75%). MS(ES) m/z 441 [M−H].

EXAMPLE 28 Preparation of3-hydroxy-4-{[5-hydroxy-1-(4-iodophenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

a) 1-(4-Iodophenyl)-3-methyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting4-iodophenylhydrazine for 2-hydrazinopyridine, the title compound wasprepared (0.60 g; 17%). MS(ES) m/z 301 [M+H].

b)3-Hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 28a) for 2-naphthol, the title compound was prepared as ared solid (0.50 g; 45%). MS(ES) m/z 549 [M−H].

EXAMPLE 29 Preparation of3-hydroxy-4-{[5-hydroxy-3-methyl-1-(2-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

a) 3-Methyl-1-(2-nitrophenyl)-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting2-nitrophenylhydrazine for 2-hydrazinopyridine, the title compound wasprepared (1.84 g; 45%). MS(ES) m/z 261 [M+CH₃CN+H].

b)3-Hydroxy-4-{[5-hydroxy-3-methyl-1-(2-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 29a) for 2-naphthol, the title compound was prepared as ared solid (0.067 g; 5%). MS(ES) m/z 468 [M−H].

EXAMPLE 30 Preparation of4-{[1-(3,4-dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

a) 1-(3,4-Dimethylphenyl)-1H,4H-pyrazolin-3,5-dione

A solution of 3,4-dimethylphenylhydrazine (8.15 g; 0.06 mol.) anddiethyl malonate (11.5 g; 0.072 mol.) in anhydrous toluene (40.0 mL) wastreated with sodium hydride (60%, pre-washed with hexanes) (0.45 g;0.072 mol.) and heated under reflux with stirring and with removal ofwater through use of a Dean-Stark apparatus for 4 h.

Ethyl acetate and water were added and the mixture filtered to removeinsoluble impurities. The bi-phasic filtrate was then acidified with 3Maqu. hydrochloric acid and filtered to afford the title compound (1.0 g;8%) as an orange powder. MS(ES) m/z 205 [M+H].

b) 1-(3,4-Dimethylphenyl)-3-ethoxy-3-pyrazolin-5-one

A solution of the compound from Example 30a) (0.315 g; 1.5 mmol.) inethanol (15.0 mL) was treated with 3 drops of concentrated sulfuric acidthen heated under reflux with stirring and with removal of water throughuse of a Dean-Stark apparatus containing 3 Å molecular sieves for 24 h.

The reaction was cooled and quenched by addition of water. The mixturewas then evaporated to give a solid which was purified by chromatography(silica gel, step gradient, 0-2% methanol/chloroform) to afford thetitle compound (0.172 g; 48%) as a yellow solid. MS(ES) m/z 233 [M+H].

c)4-{[1-(3,4-Dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 30b) for 2-naphthol, the title compound was prepared as ared solid (60 mg; 26%). MS(ES) m/z 481 [M−H].

EXAMPLE 31

Preparation of3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

a) 3-Methyl-1-(4-trifluoromethylphenyl)-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting4-trifluoromethylphenylhydrazine for 2-hydrazinopyridine, the titlecompound was prepared (3.25 g; 93%). MS(ES) m/z 243 [M+H].

b)3-Hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 31a) for 2-naphthol, the title compound was prepared as ared solid (1.64 g; 77%). MS(ES) m/z 491 [M−H].

EXAMPLE 32 Preparation of3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

a) 3-Methyl-1-(3-methylphenyl)-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting3-methylphenylhydrazine for 2-hydrazinopyridine, the title compound wasprepared (2.82 g; 90%). MS(ES) m/z 189 [M+H].

b)3-Hydroxy-4-{[5-hydroxy-3-methyl-1-(3-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 32a) for 2-naphthol, the title compound was prepared as ared solid (1.2 g; 49%). MS(ES) m/z 437 [M−H].

EXAMPLE 33 Preparation of4-{[3-tert-butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

a) 3-tert-Butyl-1-(3,4-dimethylphenyl)-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting3,4-dimethylphenylhydrazine for 2-hydrazinopyridine and ethyltert-butylacetate for ethyl acetoacetate, the title compound wasprepared (25.1 g; 99%). MS(ES) m/z 245 [M+H].

b)4-{[3-tert-Butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 25a) for 2-naphthol, the title compound was prepared as ared solid 3.4 g; 84%). MS(ES) m/z 493 [M−H].

EXAMPLE 34 Preparation of4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

a) 1-(3,4-Dimethylphenyl)-3-phenyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting3,4-dimethylphenylhydrazine for 2-hydrazinopyridine and ethylbenzoylacetate for ethyl acetoacetate, the title compound was prepared(16.0 g; 61%). MS(ES) m/z 265 [M+H].

b)4-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 25a) for 2-naphthol, the title compound was prepared as ared solid (2.1 g; 34%). MS(ES) m/z 513 [M−H].

EXAMPLE 35 Preparation of4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-napthalenecarboxylicacid

a) 4-Diazo-1-(3,4-dimethylphenyl)-3-methyl-3-pyrazolin-5-one

A methanol solution of the compound of Example 25a) (0.85 g, 4.19 mmol)and tosyl azide (0.84 g, 4.19 mmol) was treated with triethylamine (0.42g, 4.19 mmol). The reaction was stirred at room temperature for 2 hours.It was concentrated and applied to a silica gel column and washed withethylacetate and hexanes to give the title compound as yellow powder(0.5 g, 53%). MS(ES) m/z 229 [M+H]⁺. HPLC t_(R) 7.2 min [Ultrasphere®ODS, 4.6×250 mm, 2 mL/min, gradient 20-90% acetonitrile/water (0.1% TFA)during 12 min, UV detection at 254 nM].

b)4-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-napthalenecarboxylicacid

To a solution of the compound from Example 14c) (0.030 g, 0.13 mmol) andthe compound from Example 35a) (27 mg, 0.13 mmol) in ethanol (3.0 mL)was added triethylamine (0.30 mL). The reaction was stirred at roomtemperature for 7d. The solution was concentrated and acidified with 1NHCl. The precipitate was filtered and purified by chromatography [ODS,step gradient, 10-90% acetonitrile/water (0.1% TFA)] to give the titlecompound as red powder (0.020 g, 36%). MS(ES) m/z 431 [M+H]⁺, HPLC t_(R)6.9 min [Ultrasphere® ODS, 4.6×250 mm, 2 mL/min, gradient 20-90%acetonitrile/water (0.1% TFA) during 11 min, UV detection at 254 nM].

EXAMPLE 36 Preparation of methyl5-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-6-hydroxy-2-napthalenecarboxylate

Following the procedure of Example 35b) except substituting methyl 6hydroxy-2-naphthalenecarboxylate for 3-hydroxy-1-naphthalenecarboxylicacid, the title compound was prepared as red powder (0.020 g, 36%).MS(ES) m/z 431 [M+H]⁺, HPLC t_(R) 10.4 min [Ultrasphere® ODS, 4.6×250mm, 2 mL/min, gradient 40-90% acetonitrile/water (0.1% TFA) during 11min, UV detection at 254 nM].

EXAMPLE 37 Preparation of1-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-2hydroxynaphthalene

Following the procedure of Example 35b) except substituting2-hydroxynaphthalene for 3-hydroxy-1-naphthalenecarboxylic acid, thetitle compound was prepared as red powder (0.039 g, 70%). MS(ES) m/z 373[M+H]⁺, HPLC t_(R) 10.8 min [Ultrasphere® ODS, 4.6×250 mm, 2 mL/min,gradient 40-90% acetonitrile/water (0.1 % TFA) during 11 min, UVdetection at 254 nM].

EXAMPLE 38 Preparation of3-hydroxy-4-({5-hydroxy-1-[(4-methanesulfonyl)phenyl]-3-methyl-1H-pyrazol-4-yl}azo)-1-naphthalenesulfonicacid

a) 1-(4-Methanesulfonylphenyl)-3-methyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting4-methanesulfonylphenylhydrazine for 2-hydrazinopyridine, the titlecompound was prepared (1.1 g; 50%). MS(ES) m/z 253 [M+H]⁺.

b)3-Hydroxy-4-({5-hydroxy-1-[(4-methanesulfonyl)phenyl]-3-methyl-1H-pyrazol-4-yl}azo)-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 38a) for 2-naphthol, the title compound was prepared as ared solid (0.158 g; 17%). MS(ES) m/z 501 [M−H]⁻.

EXAMPLE 39 Preparation of4-[(1-benzyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid

a) 1-Benzyl-3-methyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except substitutingbenzylhydrazine for 2-hydrazinopyridine, the title compound was prepared(0.74 g; 77%). MS(ES) m/z 189 [M+H]⁺.

b)4-[(1-Benzyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 39a) for 2-naphthol, the title compound was prepared as ared solid (0.07 g; 30%). MS(ES) m/z 437 [M−H]⁻.

EXAMPLE 40 Preparation of4-({1-[4-(aminosulfonyl)phenyl]-5-hydroxy-3-methyl-1H-pyrazol-4-yl}azo)-3-hydroxy-1-naphthalenesulfonicacid

a) 1-[4-(Aminosulfonyl)phenyl]-3-methyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except substituting(4-aminosulfonyl)phenylhydrazine for 2-hydrazinopyridine, the titlecompound was prepared (0.1.26 g; 74%). MS(ES) m/z 254 [M+H]⁺.

b)4-({1-[4(Aminosulfonyl)phenyl]-5-hydroxy-3-methyl-1H-pyrazol-4-yl}azo)-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 40a) for 2-naphthol, the title compound was prepared as ared solid (0.101 g; 34%). MS(ES) m/z 502 [M−H]⁻.

EXAMPLE 41 Preparation of4-[(1-tert-butyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid

a) 1-tert-Butyl-3-methyl-3-pyrazolin-5-one

Following the procedure of Example 22a), except substitutingtert-butylhydrazine for 2-hydrazinopyridine, the title compound wasprepared (0.90 g; 73%). MS(ES) m/z 155 [M+H]⁺.

b)4-[(1-tert-Butyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid

Following the procedure of Example 1, except substituting the compoundfrom Example 41a) for 2-naphthol, the title compound was prepared as ared solid (0.0663 g; 24%). MS(ES) m/z 403 [M−H]⁻.

EXAMPLE 42 Capsule Composition

An oral dosage form for administering a presently invented agonist ofthe TPO receptor is produced by filing a standard two piece hard gelatincapsule with the ingredients in the proportions shown in Table I, below.

TABLE I INGREDIENTS AMOUNTS3-hydroxy-4-[(4-hydroxy-2-methoxy-1-naphthalenyl)azo]-1- 25 mgnaphthalenesulfonic acid (Compound 1) Lactose 55 mg Talc 16 mg MagnesiumStearate  4 mg

EXAMPLE 43 Injectable Parenteral Composition

An injectable form for administering a presently invented agonist of theTPO receptor is produced by stirring 1.5% by weight of3-hydroxy-4[-(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid, monosodium salt (Compound 2) in 10% by volume propylene glycol inwater.

EXAMPLE 44 Tablet Composition

The sucrose, calcium sulfate dihydrate and a presently invented agonistof the TPO receptor, as shown in Table II below, are mixed andgranulated in the proportions shown with a 10% gelatin solution. The wetgranules are screened, dried, mixed with the starch, talc and stearicacid, screened and compressed into a tablet.

TABLE II INGREDIENTS AMOUNTS3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-methylphenyl)-1H- 20 mg pyrazol-4-yl]azo}-1-napthalenecarboxylic acid (Compound 3) calciumsulfate dihydrate 30 mg  sucrose 4 mg starch 2 mg talc 1 mg stearic acid0.5 mg  

Preferred among the compounds of the Examples are compounds of Examples9, 23, 27, 32 and 33.

Most preferred among the compounds of the Examples are compounds ofExamples 24, 25, 28, 30 and 31.

While the preferred embodiments of the invention are illustrated by theabove, it is to be understood that the invention is not limited to theprecise instructions herein disclosed and that the right to allmodifications coming within the scope of the following claims isreserved.

What is claimed is:
 1. A method of treating of thrombocytopenia in amammal in need thereof which comprises administering to such mammal atherapeutically effective amount of a compound of Formula (II)

wherein: R, R¹, R², R³, R⁴ and R⁵ are each independently selected fromhydrogen, —C(O)OR⁶, —CONR⁹R¹⁰, —SO₂NR⁹R¹⁰, phosphonic acid, phosphinicacid, C₁₋₆alkyl, C₁₋₆alkoxy, —(CH₂)_(p)OR⁶, nitro, cyano, halogen,—NR⁹R¹⁰, N-acylamino, N-sulfonylamino, —S(O)_(n)R⁶, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, alkyl, cycloalkyl, substituted cycloalkyl,protected —OH, and alkyl substituted with one or more substituentsselected from the group consisting of alkoxy, acyloxy, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, —NR⁹R¹⁰, N-acylamino, oxo, hydroxy, cycloalkyl,substituted cycloalkyl, —C(O)OR⁶, —C(O)NR⁹R¹⁰, —S(O)₂NR⁹R¹⁰,—S(O)_(n)R⁶, aryloxy, nitro, cyano, halogen, and protected —OH; where nis 0 to 3; p is 0-6; R⁶ is selected from hydrogen, alkyl, cycloalkyl,C₆-C₁₂aryl, substituted alkyl, substituted cycloalkyl and substitutedC₆-C₁₂aryl, and R⁹ and R¹⁰ are independently selected from hydrogen,cycloalkyl, C₆-C₁₂aryl, substituted cycloalkyl, substituted C₆-C₁₂aryl,alkyl or alkyl substituted with one or more substituents selected fromthe group consisting of alkoxy, acyloxy, aryloxy, —NR⁶R⁶, N-acylamino,oxo, hydroxy, —C(O)OR⁶, —S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro,cyano, halogen, cycloalkyl, substituted cycloalkyl, C₅-C₁₂aryl,substituted C₅-C₁₂aryl and protected —OH where n and R⁶ are as describedabove; or R⁹ and R¹⁰ taken together with the nitrogen to which they areattached represent a 5 to 6 member saturated ring containing up to oneother heteroatom selected from oxygen and nitrogen; m is 0-6; and AR isselected from the group consisting of naphthalene, phenyl, pyrazole andphenanthrene; each of which is optionally substituted with one or moresubstituents selected from the group consisting of alkyl, cycloalkyl,substituted cycloalkyl, C₅-C₁₂aryl, substituted C₅-C₁₂aryl, aryloxy,hydroxy, alkoxy, acyloxy, —NR⁷R⁸, N-acylamino, N-sulfonylamino, nitro,cyano, halogen, —C(O)OR⁶, —C(O)NR⁷R⁸, —S(O)₂NR⁷R⁸, —S(O)_(n)R⁶,protected —OH, and alkyl substituted with one or more substituentsselected from the group consisting of alkoxy, acyloxy, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, —NR⁶R⁶, N-acylamino, oxo, hydroxy, cycloalkyl,substituted cycloalkyl, —C(O)OR⁶, —C(O)NR⁷R⁸, —S(O)₂NR⁷R⁸, —S(O)_(n)R⁶,aryloxy, nitro, cyano, halogen, and protected —OH; where n is 0 to 3; R⁶is selected from hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substitutedalkyl, substituted cycloalkyl and substituted C₆-C₁₂aryl; and R⁷ and R⁸are independently hydrogen, cycloalkyl, C₆-C₁₂aryl, substitutedcycloalkyl, substituted C₆-C₁₂aryl, alkyl or alkyl substituted with oneor more substituents selected from the group consisting of alkoxy,acyloxy, aryloxy, —NR⁶R⁶, N-acylamino, oxo, hydroxy, —C(O)OR⁶,—S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro, cyano, cycloalkyl,substituted cycloalkyl, halogen, C₆-C₁₂aryl, substituted C₆-C₁₂aryl andprotected —OH where n and R⁶ are as described above; andpharmaceutically acceptable salts, hydrates, solvates and estersthereof.
 2. A method of claim 1 wherein the mammal is a human.
 3. Themethod of claim 2 wherein the compound is selected from3-hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo-]-1-naphthalenesulfonic acid;3-hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid;3-hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid;3-hydroxy-4-[(2-hydroxy-5-methyl-1-phenyl)azo]-1-naphthalenesulfonicacid; 3-hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-1-naphthalenesulfonicacid;3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid;3-hydroxy-4-[(10-hydroxy-9-phenanthrenyl)azo]-1-naphthalenesulfonicacid;3-hydroxy-4-[(2-hydroxy-7-methoxy-1-naphthalenyl)azo]-1-naphthalenesulfonicacid;3-hydroxy-4-[(4-hydroxy-2-methoxy-1-naphthalenyl)azo]-1-naphthalenesulfonicacid;4-[(1,3-dimethyl-5-hydroxy-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-1-(4-methylphenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenecarboxylicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenecarboxylicacid;4-{1-[3-(N-ethylsulfonamidophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-[(3-ethoxycarbonyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[3-tert-butyl-5-hydroxy-1-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-[(3-ethoxy-5-hydroxy-1-(4-nitrophenyl)-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;4-{[3-tert-butyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-[(5-hydroxy-3-methyl-1-pyridin-2-yl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid;4-{[1-(4-benzyloxyphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(4-fluorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-1-(4-iodophenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(2-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;3-hydroxy-4-{[(5-hydroxy-3-methyl-1-(3-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[3-tert-butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-napthalenecarboxylicacid; Methyl5-{[1-(3,4dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-6-hydroxy-2-napthalenecarboxylate;1-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-2-hydroxynaphthalene;3-Hydroxy-4-({5-hydroxy-1-[(4-methanesulfonyl)phenyl]-3-methyl-1H-pyrazol-4-yl}azo)-1-naphthalenesulfonicacid;4-[(1-Benzyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;4-({1-[4-(Aminosulfonyl)phenyl}-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo)-3-hydroxy-1-naphthalenesulfonicacid; and4-[(1-tert-Butyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid; and pharmaceutically acceptable salts, hydrates, solvates andesters thereof.
 4. The method of claim 3 wherein the compound isselected from4-{[3-tert-butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-1-(4-iodophenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid; and4-{[1-(3,4-dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid; and pharmaceutically acceptable salts, hydrates, solvates andesters thereof.
 5. The method of claim 1 wherein the compound isadministered orally.
 6. The method of claim 1 wherein the compound isadministered parenterally.
 7. A method of enhancing platelet productionin a mammal in need thereof which comprises administering to such mammala therapeutically effective amount of a compound of Formula (II)

wherein: R, R¹, R², R³, R⁴ and R⁵ are each independently selected fromhydrogen, —C(O)OR⁶, —CONR⁹R¹⁰, —SO₂NR⁹R¹⁰, phosphonic acid, phosphinicacid, C₁₋₆alkyl, C₁₋₆alkoxy, —(CH₂)_(p)OR⁶, nitro, cyano, halogen,—NR⁹R¹⁰, N-acylamino, N-sulfonylamino, —S(O)_(n)R⁶, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, alkyl, cycloalkyl, substituted cycloalkyl,protected —OH, and alkyl substituted with one or more substituentsselected from the group consisting of alkoxy, acyloxy, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, —NR⁹R¹⁰, N-acylamino, oxo, hydroxy, cycloalkyl,substituted cycloalkyl, —C(O)OR⁶, —C(O)NR⁹R¹⁰, —S(O)₂NR⁹R¹⁰,—S(O)_(n)R⁶, aryloxy, nitro, cyano, halogen, and protected —OH; where nis 0 to 3; p is 0-6; R⁶ is selected from hydrogen, alkyl, cycloalkyl,C₆-C₁₂aryl, substituted alkyl, substituted cycloalkyl and substitutedC₆-C₁₂aryl, and R⁹ and R¹⁰ are independently selected from hydrogen,cycloalkyl, C₆-C₁₂aryl, substituted cycloalkyl, substituted C₆-C₁₂aryl,alkyl or alkyl substituted with one or more substituents selected fromthe group consisting of alkoxy, acyloxy, aryloxy, —NR⁶R⁶, N-acylamino,oxo, hydroxy, —C(O)OR⁶, —S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro,cyano, halogen, cycloalkyl, substituted cycloalkyl, C₅-C₁₂aryl,substituted C₅-C₁₂aryl and protected —OH where n and R⁶ are as describedabove; or R⁹ and R¹⁰ taken together with the nitrogen to which they areattached represent a 5 to 6 member saturated ring containing up to oneother heteroatom selected from oxygen and nitrogen; m is 0-6; and AR isselected from the group consisting of naphthalene, phenyl, pyrazole andphenanthrene; each of which is optionally substituted with one or moresubstituents selected from the group consisting of alkyl, cycloalkyl,substituted cycloalkyl, C₅-C₁₂aryl, substituted C₅-C₁₂aryl, aryloxy,hydroxy, alkoxy, acyloxy, —NR⁷R⁸, N-acylamino, N-sulfonylamino, nitro,cyano, halogen, —C(O)OR⁶, —C(O)NR⁷R⁸, —S(O)₂NR⁷R⁸, —S(O)_(n)R⁶,protected —OH, and alkyl substituted with one or more substituentsselected from the group consisting of alkoxy, acyloxy, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, —NR⁶R⁶, N-acylamino, oxo, hydroxy, cycloalkyl,substituted cycloalkyl, —C(O)OR⁶, —C(O)NR⁷R⁸, —S(O)₂NR⁷R⁸, —S(O)_(n)R⁶,aryloxy, nitro, cyano, halogen, and protected —OH; where n is 0 to 3; R⁶is selected from hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substitutedalkyl, substituted cycloalkyl and substituted C₆-C₁₂aryl; and R⁷ and R⁸are independently hydrogen, cycloalkyl, C₆-C₁₂aryl, substitutedcycloalkyl, substituted C₆-C₁₂aryl, alkyl or alkyl substituted with oneor more substituents selected from the group consisting of: alkoxy,acyloxy, aryloxy, —NR⁶R⁶, N-acylamino, oxo, hydroxy, —C(O)OR⁶,—S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro, cyano, cycloalkyl,substituted cycloalkyl, halogen, C₆-C₁₂aryl, substituted C₆-C₁₂aryl andprotected —OH where n and R⁶ are as described above; andpharmaceutically acceptable salts, hydrates, solvates and estersthereof.
 8. A method of claim 7 wherein the mammal is a human.
 9. Themethod of claim 8 wherein the compound is selected from3-hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo]-1-naphthalenesulfonic acid;3-hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid;3-hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonicacid;3-hydroxy-4-[(2-hydroxy-5-methyl-1-phenyl)azo]-1-naphthalenesulfonicacid; 3-hydroxy-4-[(1-hydroxy-2-naphthalenyl)azo]-1-naphthalenesulfonicacid;3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid;3-hydroxy-4-[(10-hydroxy-9-phenanthrenyl)azo]-1-naphthalenesulfonicacid;3-hydroxy-4-[(2-hydroxy-7-methoxy-1-naphthalenyl)azo]-1-naphthalenesulfonicacid;3-hydroxy-4-[(4-hydroxy-2-methoxy-1-naphthalenyl)azo]-1-naphthalenesulfonicacid;4-[(1,3-dimethyl-5-hydroxy-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-1-(4-methylphenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenecarboxylicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenecarboxylicacid;4-[1-[3-(N-ethylsulfonamidophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-[(3-ethoxycarbonyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[3-tert-butyl-5-hydroxy-1-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid4-[(3-ethoxy-5-hydroxy-1-(4-nitrophenyl)-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;4-{[3-tert-butyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-[(5-hydroxy-3-methyl-1-pyridin-2-yl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid;4-{[1-(4-benzyloxyphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(4-fluorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-1-(4-iodophenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid; 3-hydroxy-4-{[5-hydroxy-3-methyl-1-(2-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonic acid;4-{[1-(3,4dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[3-tert-butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-napthalenecarboxylicacid; Methyl5-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-6-hydroxy-2-napthalenecarboxylate;1-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-2-hydroxynaphthalene;3-Hydroxy-4-({5-hydroxy-1-[(4-methanesulfonyl)phenyl]-3-methyl-1H-pyrazol-4-yl}azo)-1-naphthalenesulfonicacid;4-[(1-Benzyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid;4-({1-[4-(Aminosulfonyl)phenyl]-5-hydroxy-3-methyl-1H-pyrazol-4-yl}azo)-3-hydroxy-1-naphthalenesulfonicacid; and4-[(1-tert-Butyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid; and pharmaceutically acceptable salts, hydrates, solvates andesters thereof.
 10. A method of agonizing the TPO receptor in a mammalin need thereof which comprises administering an effective amount of acompound of Formula (II)

wherein: R, R¹, R², R³, R⁴ and R⁵ are each independently selected fromhydrogen, —C(O)OR⁶, —CONR⁹R¹⁰, —SO₂NR⁹R¹⁰, phosphonic acid, phosphinicacid, C₁₋₆alkyl, C₁₋₆alkoxy, —(CH₂)_(p)OR⁶, nitro, cyano, halogen,—NR⁹R¹⁰, N-acylamino, N-sulfonylamino, —S(O)_(n)R⁶, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, alkyl, cycloalkyl, substituted cycloalkyl,protected —OH, and alkyl substituted with one or more substituentsselected from the group consisting of alkoxy, acyloxy, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, —NR⁹R¹⁰, N-acylamino, oxo, hydroxy, cycloalkyl,substituted cycloalkyl, —C(O)OR⁶, —C(O)NR⁹R¹⁰, —S(O)₂NR⁹R¹⁰,—S(O)_(n)R⁶, aryloxy, nitro, cyano, halogen, and protected —OH; where nis 0 to 3; p is 0-6; R⁶ is selected from hydrogen, alkyl, cycloalkyl,C₆-C₁₂aryl, substituted alkyl, substituted cycloalkyl and substitutedC₆-C₁₂aryl, and R⁹ and R¹⁰ are independently selected from hydrogen,cycloalkyl, C₆-C₁₂aryl, substituted cycloalkyl, substituted C₆-C₁₂aryl,alkyl or alkyl substituted with one or more substituents selected fromthe group consisting of alkoxy, acyloxy, aryloxy, —NR⁶R⁶, N-acylamino,oxo, hydroxy, —C(O)OR⁶, —S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro,cyano, halogen, cycloalkyl, substituted cycloalkyl, C₅-C₁₂aryl,substituted C₅-C₁₂aryl and protected —OH where n and R⁶ are as describedabove; or R⁹ and R¹⁰ taken together with the nitrogen to which they areattached represent a 5 to 6 member saturated ring containing up to oneother heteroatom selected from oxygen and nitrogen; m is 0-6; and AR isselected from the group consisting of: naphthalene, phenyl, pyrazole andphenanthrene; each of which is optionally substituted with one or moresubstituents selected from the group consisting of alkyl, cycloalkyl,substituted cycloalkyl, C₅-C₁₂aryl, substituted C₅-C₁₂aryl, aryloxy,hydroxy, alkoxy, acyloxy, —NR⁷R⁸, N-acylamino, N-sulfonylamino, nitro,cyano, halogen, —C(O)OR⁶, —C(O)NR⁷R⁸, —S(O)₂NR⁷R⁸, —S(O)_(n)R⁶,protected —OH, and alkyl substituted with one or more substituentsselected from the group consisting of: alkoxy, acyloxy, C₅-C₁₂aryl,substituted C₅-C₁₂aryl, —NR⁶R⁶, N-acylamino, oxo, hydroxy, cycloalkyl,substituted cycloalkyl, —C(O)OR⁶, —C(O)NR⁷R⁸, —S(O)₂NR⁷R⁸, —S(O)_(n)R⁶,aryloxy, nitro, cyano, halogen, and protected —OH; where n is 0 to 3; R⁶is selected from hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substitutedalkyl, substituted cycloalkyl and substituted C₆-C₁₂aryl; and R⁷ and R⁸are independently hydrogen, cycloalkyl, C₆-C₁₂aryl, substitutedcycloalkyl, substituted C₆ 14 C₁₂aryl, alkyl or alkyl substituted withone or more substituents selected from the group consisting of: alkoxy,acyloxy, aryloxy, —NR⁶R⁶, N-acylamino, oxo, hydroxy, —C(O)OR⁶,—S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro, cyano, cycloalkyl,substituted cycloalkyl, halogen, C₆-C₁₂aryl, substituted C₆-C12aryl andprotected —OH where n and R⁶ are as described above; andpharmaceutically acceptable salts, hydrates, solvates and estersthereof.
 11. A method of claim 10 wherein the mammal is a human.
 12. Acompound represented by the following Formula (I)

wherein: R, R¹, R², R³, R⁴, R⁵ and R¹ are each independently selectedfrom hydrogen, —C(O)OR⁶, —CONR⁹R¹⁰, phosphonic acid, phosphinic acid,C₁₋₆alkyl, C₁₋₆alkoxy, —(CH₂)_(p)OR⁶, nitro, cyano, halogen, —NR⁹R¹⁰,N-acylamino, N-sulfonylamino, —S(O)_(n)R⁶, C₅-C₁₂aryl, substitutedC₅-C₁₂aryl, alkyl, cycloalkyl, substituted cycloalkyl, protected —OH,and alkyl substituted with one or more substituents selected from thegroup consisting of alkoxy, acyloxy, C₅-C₁₂aryl, substituted C₅-C₁₂aryl,—NR⁹R¹⁰, N-acylamino, oxo, hydroxy, cycloalkyl, substituted cycloalkyl,—C(O)OR⁶, —C(O)NR⁹R¹⁰, —S(O)₂NR⁹R¹⁰, —S(O)_(n)R⁶, aryloxy, nitro, cyano,halogen, and protected —OH; where n is 0-3; p is 0-6; R⁶ is selectedfrom hydrogen, alkyl, cycloalkyl, C₆-C₁₂aryl, substituted alkyl,substituted cycloalkyl and substituted C₆-C₁₂aryl; and R⁹ and R¹⁰ areindependently selected from hydrogen, cycloalkyl, C₆-C₁₂aryl,substituted cycloalkyl, substituted C₆-C₁₂aryl, alkyl or alkylsubstituted with one or more substituents selected from the groupconsisting of alkoxy, acyloxy, aryloxy, —NR⁶R⁶, N-acylamino, oxo,hydroxy, —C(O)OR⁶, —S(O)_(n)R⁶, —C(O)NR⁶R⁶, —S(O)₂NR⁶R⁶, nitro, cyano,cycloalkyl, substituted cycloalkyl, C₅-C₁₂aryl, substituted C₅-C₁₂aryland protected —OH where n and R⁶ are as described above; or R⁹ and R¹⁰taken together with the nitrogen to which they are attached represent a5 to 6 member saturated ring containing up to one other heteroatomselected: from oxygen and nitrogen; m is 0-6; and R¹² is a cyclic orpolycyclic aromatic ring containing from 3 to 16 carbon atoms,optionally containing one or more heteroatoms, provided that when thenumber of carbon atoms is 3 the aromatic ring contains at least twoheteroatoms and when the number of carbon atoms is 4 the aromatic ringat least one heteroatom, and optionally substituted with one or moresubstituents selected from the group consisting of: alkyl, cycloalkyl,substituted cycloalkyl, C₅-C₁₂aryl, substituted C₅-C₁₂aryl, aryloxy,alkoxy, acyloxy, amino, nitro, cyano, halogen, hydroxy, protected —OH,and alkyl substituted with one or more substituents selected from thegroup consisting of: alkoxy, acyloxy, C₅-C₁₂aryl, substitutedC₅-C₁₂aryl, cycloalkyl, substituted cycloalkyl, aryloxy, amino, nitro,cyano, halogen, hydroxy, and protected —OH; and pharmaceuticallyacceptable salts, hydrates, solvates and esters thereof; provided that:at least one of R, R¹, R², R³, R⁴, R⁵ or R¹¹ is selected from: sulfonicacid, —C(O)OR⁶, —CONR⁹R¹⁰, phosphonic acid and phosphinic acid; whereR⁶, R⁹ and R¹⁰ are as described above; and provided that: when R issulfonic acid, R¹² does not equal unsubstituted phenyl or4-methylphenyl.
 13. A compound of claim 12 selected from3-hydroxy-4-[(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)azo]-1-naphthalenecarboxylicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenecarboxylicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[3-tert-butyl-5-hydroxy-1-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-{[3-tert-butyl-5-hydroxy-1-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-[(5-hydroxy-3-methyl-1-pyridin-2-yl-1H-pyrazol-4-yl)azo]-1-naphthalenesulfonicacid;4-{[1-(4-benzyloxyphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(4-fluorophenyl)-5-hydroxy-3-methyl-1pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-1-(4-iodophenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(2-nitrophenyl)-1H-pyrazol-4-yl]azo}-1-napthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(4-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-methylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[3-tert-butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-phenyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;4-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-napthalenecarboxylicacid; Methyl5-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-6-hydroxy-2-napthalenecarboxylate;1-{[1-(3,4-Dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-2-hydroxynaphthalene;and4-[(1-Benzyl-5-hydroxy-3-methyl-1H-pyrazol-4-yl)azo]-3-hydroxy-1-naphthalenesulfonicacid; and pharmaceutically acceptable salts, hydrates, solvates andesters thereof.
 14. A compound of claim 13 selected from4-{[3-tert-butyl-1-(3,4-dimethylphenyl)-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-3-methyl-1-(3-trifluoromethylphenyl)-1H-pyrazol-4-yl]azo}-1-naphthalenesulfonicacid;4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid;3-hydroxy-4-{[5-hydroxy-1-(4-iodophenyl)-3-methyl-1H-pyrazol-4-yl]azo}-1-napthalenesulfonicacid; and4-{[1-(3,4-dimethylphenyl)-3-ethoxy-5-hydroxy-1H-pyrazol-4-yl]azo}-3-hydroxy-1-naphthalenesulfonicacid; and pharmaceutically acceptable salts, hydrates, solvates andesters thereof.
 15. A pharmaceutical composition comprising atherapeutically effective amount of a compound according to claim 12 andat least one pharmaceutically acceptable carrier or diluent.